MINOR: quic-be: Parse, store and reuse tokens provided by NEW_TOKEN
Add ->tok and ->toklen to store these tokens into the server SSL ctx cache.
Parse at packet level (from qc_parse_ptk_frms()) these tokens and store
them calling qc_try_store_new_token() newly implemented function.
Modify qc_do_build_pkt() to resend these token calling quic_enc_token()
implemented by this patch.
Rename ->data qf_new_token struct field to ->w_data to distinguish it from
->r_data new field used to parse the NEW_TOKEN frame. Indeed to build the
NEW_TOKEN we need to write it to a static buffer into the frame struct. To
parse it we only need to store the address of the token field into the
RX buffer.
WIP: TO CHECK!!! quic-be: Start asap the mux for 0-RTT
The mux is created and woken up as soon as possible. This means as soon as
the TX early data encryption level keys are installed. These keys are
installed on the first SSL_do_handshake() call. This call is done as soon
as the connection is created.
This way the mux is able to send 0-RTT packets alongside Initial packets.
MINOR: quic-be: validate the 0-RTT transport parameters
During 0-RTT sessions, some server transport parameters are reused after having
been save from previous sessions. These parameters must not be reduced
when it resends them. The client must check this is the case when some early data
are accepted by the server. This is what is implemented by this patch.
Implement qc_early_tranport_params_validate() which checks the new server parameters
are not reduced.
Also implement qc_ssl_eary_data_accepted() which was not implemented for TLS
stack without 0-RTT support (for instance wolfssl). That said this function
was no more used. This is why the compilation against wolfssl could not fail.
This patch allows the use of 0-RTT feature on QUIC server lines with "allow-0rtt"
option. In fact 0-RTT is really enabled only if ssl_sock_srv_try_reuse_sess()
successfully manages to reuse the SSL session and the chosen application protocol
from previous connections.
Note that, at this time, 0-RTT works only with quictls and aws-lc as TLS stack.
(0-RTT does not work at all (even for QUIC frontends) with libressl).
MINOR: quic-be: qc_send_mux() adaptation for 0-RTT
When entering this function, a selection is done about the encryption level
to be used to send data. For a client, the early data encryption level
is used to send 0-RTT if this encryption level is initialized.
The Initial encryption is also registered to the send list for clients if there
is Initial crypto data to send. This allow Initial and 0-RTT packets to
be coalesced by datagrams.
MINOR: quic-be: modify ssl_sock_srv_try_reuse_sess() to reuse backend session (0-RTT)
This function is called for both TCP and QUIC connections to reuse SSL sessions
saved by ssl_sess_new_srv_cb() callback called upon new SSL session creation.
In addition to this, a QUIC SSL session must reused the ALPN and some 0-RTT QUIC
transport parameters. This is what is added by this patch for QUIC 0-RTT SSL sessions.
Note that for now on, ssl_sock_srv_try_reuse_sess() may fail for QUIC connection
if it did not managed to reuse the ALPN. The caller must be informed of such an
issue. It must not enable 0-RTT for the current session in this case. This is
impossible without ALPN which is required to start a mux.
ssl_sock_srv_try_reuse_sess() always succeeds for TCP connections.
MINOR: quic-be: Save the backend parameters (0-RTT)
For both TCP and QUIC connections, this is ssl_sess_new_srv_cb() callback which
is called when a new SSL session. Its role is to save the session to be reused
during the SSL session resumption and 0-RTT session.
This patch modifies this callback to same the QUIC parameters to be reused
for the next 0-RTT sessions (or SSL session resumption).
A new ->alpn member is added to the reused_sess objects allocated by thread
and server alongsise ->tps new quic_early_transport_params struct used to
save the QUIC transport parameters to be reused for 0-RTT sessions.
MINOR: quic-be: helper quic_reuse_srv_params() function to reuse server params (0-RTT)
Implement quic_reuse_srv_params() whose role it to reuse the ALPN used
from a first connection to a QUIC backend alongside its transport parameters
from a null terminated string <alpn> and a quic_early_transport_params struct
passed as parameters.
MINOR: quic-be: helper functions to save/restore transport params (0-RTT)
Define quic_early_transport_params new struct for QUIC transport parameters
in relation with 0-RTT. This parameters must be saved during a first session to
be reused for 0-RTT next sessions.
qc_early_transport_params_cpy() copies the 0-RTT transport parameters to be
saved during a first connection to a backend. The copy is made from
a quic_transport_params struct to a quic_ealy_transport_params struct.
On the contrary, qc_early_transport_params_reuse() copies the transport parameters
to be reused for a 0-RTT session from a previous one. The copy is made
from a quic_early_transport_params strcut to a quic_transport_params struct.
Also add QUIC_EV_EARLY_TRANSP_PARAMS trace event to dump such 0-RTT
transport parameters from traces.
MINOR: quic-be: Send post handshake frames from list of frames (0-RTT)
This patch is required to make 0-RTT work. It modifies the prototype of
quic_build_post_handshake_frames() to send post handshake frames from a
list of frames in place of the application encryption level (used
as <qc->ael> local variable).
This patch does not modify at all the current QUIC stack behavior (even for
QUIC frontends). It must be considered as a preparation for the code
to come about 0-RTT support for QUIC backends.
MINOR: activity/memory: count allocations performed under a lock
By checking the current thread's locking status, it becomes possible
to know during a memory allocation whether it's performed under a lock
or not. Both pools and memprofile functions were instrumented to check
for this and to increment the memprofile bin's locked_calls counter.
This one, when not zero, is reported on "show profiling memory" with a
percentage of all allocations that such locked allocations represent.
This way it becomes possible to try to target certain code paths that
are particularly expensive. Example:
MINOR: activity: collect CPU time spent on memory allocations for each task
When task profiling is enabled, the pool alloc/free code will measure the
time it takes to perform memory allocation after a cache miss or memory
freeing to the shared cache or OS. The time taken with the thread-local
cache is never measured as measuring that time is very expensive compared
to the pool access time. Here doing so costs around 2% performance at 2M
req/s, only when task profiling is enabled, so this remains reasonable.
The scheduler takes care of collecting that time and updating the
sched_activity entry corresponding to the current task when task profiling
is enabled.
The goal clearly is to track places that are wasting CPU time allocating
and releasing too often, or causing large evictions. This appears like
this in "show profiling tasks aggr":
MINOR: activity: add a new mem_avg column to show profiling stats
This new column will be used for reporting the average time spent
allocating or freeing memory in a task when task profiling is enabled.
For now it is not updated.
MINOR: activity: collect time spent with a lock held for each task
When DEBUG_THREAD > 0 and task profiling enabled, we'll now measure the
time spent with at least one lock held for each task. The time is
collected by locking operations when locks are taken raising the level
to one, or released resetting the level. An accumulator is updated in
the thread_ctx struct that is collected by the scheduler when the task
returns, and updated in the sched_activity entry of the related task.
Here we see that almost the entirety of stktable_add_pend_updates() is
spent under a lock, that 1/3 of the execution time of process_stream()
was performed under a lock and that 2/3 of it was spent waiting for a
lock (this is related to the 10 track-sc present in this config), and
that the locking time in process_peer_sync() has now significantly
reduced. This is more visible with "show profiling tasks aggr":
MINOR: activity: add a new lkd_avg column to show profiling stats
This new column will be used for reporting the average time spent
in a task with at least one lock held. It will only have a non-zero
value when DEBUG_THREAD > 0. For now it is not updated.
MINOR: thread: add a lock level information in the thread_ctx
The new lock_level field indicates the number of cumulated locks that
are held by the current thread. It's fed as soon as DEBUG_THREAD is at
least 1. In addition, thread_isolate() adds 128, so that it's even
possible to check for combinations of both. The value is also reported
in thread dumps (warnings and panics).
MINOR: activity: collect time spent waiting on a lock for each task
When DEBUG_THREAD > 0, and if task profiling is enabled, then each
locking attempt will measure the time it takes to obtain the lock, then
add that time to a thread_ctx accumulator that the scheduler will then
retrieve to update the current task's sched_activity entry. The value
will then appear avearaged over the number of calls in the lkw_avg column
of "show profiling tasks", such as below:
MINOR: activity: add a new lkw_avg column to show profiling stats
This new column will be used for reporting the average time spent waiting
for a lock. It will only have a non-zero value when DEBUG_THREAD > 0. For
now it is not updated.
MINOR: activity: don't report the lat_tot column for show profiling tasks
This column is pretty useless, as the total latency experienced by tasks
is meaningless, what matters is the average per call. Since we'll add more
columns and we need to keep all of this readable, let's get rid of this
column.
BUG/MINOR: resolvers: Restore round-robin selection on records in DNS answers
Since the commit dcb696cd3 ("MEDIUM: resolvers: hash the records before
inserting them into the tree"), When several records are found in a DNS
answer, the round robin selection over these records is no longer performed.
Indeed, before a list of records was used. To ensure each records was
selected one after the other, at each selection, the first record of the
list was moved at the end. When this list was replaced bu a tree, the same
mechanism was preserved. However, the record is indexed using its key, a
hash of the record. So its position never changes. When it is removed and
reinserted in the tree, its position remains the same. When we walk though
the tree, starting from the root, the records are always evaluated in the
same order. So, even if there are several records in a DNS answer, the same
IP address is always selected.
It is quite easy to trigger the issue with a do-resolv action.
To fix the issue, the node to perform the next selection is now saved. So
instead of restarting from the root each time, we can restart from the next
node of the previous call.
Thanks to Damien Claisse for the issue analysis and for the reproducer.
This patch should fix the issue #3116. It must be backported as far as 2.6.
As stated by the documentation, when a do-resolv resolution is performed,
the result should be cached for <hold.valid> milliseconds. However, the only
way to cache the result is to always have a requester. When the last
requester is unlink from the resolution, the resolution is released. So, for
a do-resolv resolution, it means it could only work by chance if the same
FQDN is requested enough to always have at least two streams waiting for the
resolution. And because in that case, the cached result is used, it means
the traffic must be quite high.
In fact, a good approach to fix the issue is to keep orphan resolutions to
be able cache the result and only release them after hold.valid milliseconds
after the last real resolution. The resolver's task already releases orphan
resolutions. So we only need to check the expiration date and take care to
not release the resolution when the last stream is unlink from it.
This patch should be backported to all stable versions. We can start to
backport it as far as 3.1 and then wait a bit.
JWS functions are supposed to return 0 upon error or when nothing was
produced. This was done in order to put easily the return value in
trash->data without having to check the return value.
However functions like a2base64url() or snprintf() could return a
negative value, which would be casted in a unsigned int if this happen.
This patch add checks on the JWS functions to ensure that no negative
value can be returned, and change the prototype from int to size_t.
This patch extends the documentation for "limited-quic" global keyword.
It mentions first that it relies on USE_QUIC_OPENSSL_COMPAT=1 build
option.
Compatibility with TLS libraries is now clearly exposed. In particular,
it highlights the fact that it is mostly targetted at OpenSSL version
prior to 3.5.2, and that it should be disabled if a recent OpenSSL
release is available. It also states that limited-quic does nothing if
USE_QUIC_OPENSSL_COMPAT is not set during compilation.
MINOR: quic: display build warning for compat layer on recent OpenSSL
Build option USE_QUIC_OPENSSL_COMPAT=1 must be set to activate QUIC
support for OpenSSL prior to version 3.5.2. This compiles an internal
compatibility layer, which must be then activated at runtime with global
option limited-quic.
Starting from OpenSSL version 3.5.2, a proper QUIC TLS API is now
exposed. Thus, the compatibility layer is unneeded. However it can still
be compiled against newer OpenSSL releases and activated at runtime,
mostly for test purpose.
As this compatibility layer has some limitations, (no support for QUIC
0-RTT), it's important that users notice this situation and disable it
if possible. Thus, this patch adds a notice warning when
USE_QUIC_OPENSSL_COMPAT=1 is set when building against OpenSSL 3.5.2 and
above. This should be sufficient for users and packagers to understand
that this option is not necessary anymore.
Note that USE_QUIC_OPENSSL_COMPAT=1 is incompatible with others TLS
library which exposed a QUIC API based on original BoringSSL patches
set. A build error will prevent the compatibility layer to be built.
limited-quic option is thus silently ignored.
MINOR: quic-be: make SSL/QUIC objects use their own indexes (ssl_qc_app_data_index)
This index is used to retrieve the quic_conn object from its SSL object, the same
way the connection is retrieved from its SSL object for SSL/TCP connections.
This patch implements two helper functions to avoid the ugly code with such blocks:
#ifdef USE_QUIC
else if (qc) { .. }
#endif
Implement ssl_sock_get_listener() to return the listener from an SSL object.
Implement ssl_sock_get_conn() to return the connection from an SSL object
and optionally a pointer to the ssl_sock_ctx struct attached to the connections
or the quic_conns.
Use this functions where applicable:
- ssl_tlsext_ticket_key_cb() calls ssl_sock_get_listener()
- ssl_sock_infocbk() calls ssl_sock_get_conn()
- ssl_sock_msgcbk() calls ssl_sock_get_ssl_conn()
- ssl_sess_new_srv_cb() calls ssl_sock_get_conn()
- ssl_sock_srv_verifycbk() calls ssl_sock_get_conn()
Also modify qc_ssl_sess_init() to initialize the ssl_qc_app_data_index index for
the QUIC backends.
MINOR: quic: get rid of ->target quic_conn struct member
The ->li (struct listener *) member of quic_conn struct was replaced by a
->target (struct obj_type *) member by this commit:
MINOR: quic-be: get rid of ->li quic_conn member
to abstract the connection type (front or back) when implementing QUIC for the
backends. In these cases, ->target was a pointer to the ojb_type of a server
struct. This could not work with the dynamic servers contrary to the listeners
which are not dynamic.
This patch almost reverts the one mentioned above. ->target pointer to obj_type member
is replaced by ->li pointer to listener struct member. As the listener are not
dynamic, this is easy to do this. All one has to do is to replace the
objt_listener(qc->target) statement by qc->li where applicable.
For the backend connection, when needed, this is always qc->conn->target which is
used only when qc->conn is initialized. The only "problematic" case is for
quic_dgram_parse() which takes a pointer to an obj_type as third argument.
But this obj_type is only used to call quic_rx_pkt_parse(). Inside this function
it is used to access the proxy counters of the connection thanks to qc_counters().
So, this obj_type argument may be null for now on with this patch. This is the
reason why qc_counters() is modified to take this into consideration.
BUG/MAJOR: stream: Force channel analysis on successful synchronous send
This patchs reverts commit a498e527b ("BUG/MAJOR: stream: Remove READ/WRITE
events on channels after analysers eval") because of a regression. It was an
attempt to properly detect synchronous sends, even when the stream was woken
up on a write event. However, the fix was wrong because it could mask
shutdowns performed during process_stream() and block the stream.
Indeed, when a shutdown is performed, because an error occurred for
instance, a write event is reported. The commit above could mask this event
while the shutdown prevent any synchronous sends. In such case, the stream
could remain blocked infinitly because an I/O event was missed.
So to properly fix the original issue (#3070), the write event must not be
masked before a synchronous send. Instead, we now force the channel analysis
by setting explicitly CF_WAKE_ONCE flags on the corresponding channel if a
write event is reported after the synchronous send. CF_WRITE_EVENT flag is
remove explicitly just before, so it is quite easy to detect.
This patch must be backport to all stable version in same time of the commit
above.
MEDIUM: peers: move process_peer_sync() to a single thread
The remaining half of the task_queue() and task_wakeup() contention
is caused by this function when peers are in use, because just like
process_table_expire(), it's created using task_new_anywhere() and
is woken up for local updates. Let's turn it to single thread by
rotating the assigned threads during initialization so that a table
only runs on one thread at a time.
Here we go backwards to assign the threads, so that on small setups
they don't end up on the same CPUs as the ones used by the stick-tables.
This way this will make an even better use of large machines. The
performance remains the same as with previous patch, even slightly
better (1-3% on avg).
At this point there's almost no multi-threaded task activity anymore
(only srv_cleanup_idle_server once in a while). This should improve
the situation described by Felipe in issues #3084 and #3101.
This should be backported to 3.2 after some extended checks.
MEDIUM: stick-table: move process_table_expire() to a single thread
A big deal of the task_queue() contention is caused by this function
because it's created using task_new_anywhere() and is subject to
heavy updates. Let's turn it to single thread by rotating the assigned
threads during initialization so that a table only runs on one thread
at a time.
However there's a trick: the function used to call task_queue() to
requeue the task if it had advanced its timer (may only happen when
learning an entry from a peer). We can't do that anymore since we can't
queue another thread's task. Thus instead of the task needs to be
scheduled earlier than previously planned, we simply perform a wakeup.
It will likely do nothing and will self-adjust its next wakeup timer.
Doing so halves the number of multi-thread task wakeups. In addition
the request rate at saturation increased by 12% with 16 peers and 40
tables on a 16 8-thread processes. This should improve the situation
described by Felipe in issues #3084 and #3101.
This should be backported to 3.2 after some extended checks.
BUG/MINOR: stick-table: make sure never to miss a process_table_expire update
In stktable_requeue_exp(), there's a tiny race at the beginning during
which we check the task's expiration date to decide whether or not to
wake process_table_expire() up. During this race, the task might just
have finished running on its owner thread and we can miss a task_queue()
opportunity, which probably explains why during testing it seldom happens
that a few entries are left at the end.
Let's perform a CAS to confirm the value is still the same before
leaving. This way we're certain that our value has been seen at least
once.
MEDIUM: resolvers: make the process_resolvers() task single-threaded
This task is sometimes caught triggering the watchdog while waiting for
the infamous resolvers lock, or the scheduler's wait queue lock in
task_queue(). Both are caused by its multi-threaded capability. The
task may indeed start on a thread that's different from the one that
is currently receiving a response and that holds the resolvers lock,
and when being queued back, it requires to lock the wait queue. Both
problems disappear when sticking it to a single thread. But for configs
running multiple resolvers sections, it would be suboptimal to run them
all on the same thread. In order to avoid this, we implement a counter
in the resolvers_finalize_config() section that rotates the thread for
each resolvers section.
This was sufficient to further improve the performance here, making the
CPU usage drop to about 7% (from 11 previously or 38 initially) and not
showing any resolvers lock contention anymore in perf top output.
The change was kept fairly minimal to permit a backport once enough
testing is conducted on it. It could address a significant part of
the trouble reported by Felipe in GH issue #3101.
MEDIUM: dns: bind the nameserver sockets to the initiating thread
There's still a big architectural limitation in the dns/resolvers code
regarding threads: resolvers run as a task that is scheduled to run
anywhere, and each NS dgram socket is bound to any thread of the same
thread group as the initiating thread. This becomes a big problem when
dealing with multiple nameservers because responses arrive on any thread,
start by locking the resolvers section, and other threads dealing with
responses are just stuck waiting for the lock to disappear. This means
that most of the time is exclusively spent causing contention. The
process_resolvers() function also also suffers from this contention
but apparently less often.
It turns out that the nameserver sockets are created during emission
of the first packet, triggered from the resolvers task. The present
patch exploits this to stick all sockets to the calling thread instead
of any thread. This way there is no longer any contention between
multiple nameservers of a same resolvers section. Tests with a section
having 10 name servers showed that the CPU usage dropped from 38 to
about 10%, or almost by a factor of 4.
Note that TCP resolvers do not offer this possibility because the
tasks that manage the applets are created earlier to run anywhere
during config parsing. This might possibly be refined later, e.g.
by changing the task's affinity when it first runs.
The change was kept fairly minimal to permit a backport once enough
testing is conducted on it. It could address a significant part of
the trouble reported by Felipe in GH issue #3101.
BUG/MEDIUM: ssl: Fix a crash if we failed to create the mux
In ssl_sock_io_cb(), if we failed to create the mux, we may have
destroyed the connection, so only attempt to access it to get the ALPN
if conn_create_mux() was successful.
This fixes crashes that may happen when using ssl.
Commit 5ab9954faa9c815425fa39171ad33e75f4f7d56f introduced a new flag in
ssl_sock_ctx, to know that an ALPN was negociated, however, the way to
get the ssl_sock_ctx was wrong for QUIC. If we're using QUIC, get it
from the quic_conn.
This should fix crashes when attempting to use QUIC.
DEBUG: stick-tables: export stktable_add_pend_updates() for better reporting
This function is a tasklet handler used to send peers updates, and it can
happen quite a bit in "show tasks" and "show profiling tasks", so let's
export it so that we don't face a cryptic symbol name:
BUG/MEDIUM: stick-tables: don't loop on non-expirable entries
The stick-table expiration of ref-counted entries was insufficiently
addresse by commit 324f0a60ab ("BUG/MINOR: stick-tables: never leave
used entries without expiration"), because now entries are just requeued
where they were, so they're visited over and over for long sessions,
causing process_table_expire() to loop, eating CPU and causing lock
contention.
Here we take care of refreshing their timeer when they are met, so
that we don't meet them more than once per stick-table lifetime. It
should address at least a part of the recent degradation that Felipe
noticed in GH #3084.
Since the fix above was marked for backporting to 3.2, this one should
be backported there as well.
MINOR: tools: don't emit "+0" for symbol names which exactly match known ones
resolve_sym_name() knows a number of symbols, but when one exactly matches
(e.g. a task's handler), it systematically displays the offset behind it
("+0"). Let's only show the offset when non-zero. This can be backported
as this is helpful for debugging.
MINOR: activity: indicate the number of calls on "show tasks"
The "show tasks" command can be useful to inspect run queues for active
tasks, but currently it's difficult to distinguish an occasional running
task from a heavily active one. Let's collect the number of calls for
each of them, report them average on the number of instances of each task
as well as a percentage of the total used. This way it even becomes
possible to get a hint about how CPU usage is distributed.
BUG/MINOR: activity: fix reporting of task latency
In 2.4, "show tasks" was introduced by commit 7eff06e162 ("MINOR:
activity: add a new "show tasks" command to list currently active tasks")
to expose some info about running tasks. The latency is not correct
because it's a u32 subtracted from a u64. It ought to have been casted
to u32 for the operation, which is what this patch does.
BUILD: ssl: address a recent build warning when QUIC is enabled
Since commit 5ab9954faa ("MINOR: ssl: Add a flag to let it known we have
an ALPN negociated"), when building with QUIC we get this warning:
src/ssl_sock.c: In function 'ssl_sock_advertise_alpn_protos':
src/ssl_sock.c:2189:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
Let's just move the instructions after the optional declaration. No
backport is needed.
MEDIUM: server: Make use of the stored ALPN stored in the server
Now that which ALPN gets negociated for a given server, use that to
decide if we can create the mux right away in connect_server(), and use
it in conn_install_mux_be().
That way, we may create the mux soon enough for early data to be sent,
before the handshake has been completed.
This commit depends on several previous commits, and it has not been
deemed important enough to backport.
Willy Tarreau [Thu, 7 Aug 2025 15:32:24 +0000 (17:32 +0200)]
CLEANUP: backend: clarify the cases where we want to use early data
The conditions to use early data on output are super tricky and
detected later, so that it's difficult to figure how this works. This
patch splits the condition in two parts, the one that can be performed
early that is based on config/client/etc. It is used to clear a variable
that allows early data to be used in case any condition is not satisfied.
It was purposely split into multiple independent and reviewable tests.
The second part remains where it was at the end, and is used to temporarily
clear the handshake flags to let the data layer use early data. This one
being tricky, a large comment explaining the principle was added.
The logic was not changed at all, only the code was made more readable.
Willy Tarreau [Thu, 7 Aug 2025 15:06:45 +0000 (17:06 +0200)]
CLEANUP: backend: simplify the complex ifdef related to 0RTT in connect_server()
Since 3.0 we have HAVE_SSL_0RTT precisely to avoid checking horribly
complicated and unmaintainable conditions to detect support for 0RTT.
Let's just drop the complex condition and use the macro instead.
Willy Tarreau [Thu, 7 Aug 2025 14:30:38 +0000 (16:30 +0200)]
CLEANUP: backend: invert the condition to start the mux in connect_server()
Instead of trying to switch from delayed start to instant start based
on a single condition, let's do the opposite and preset the condition
to instant start and detect what could cause it to be delayed, thus
falling back to the slow mode. The condition remains exactly the
inverted one and better matches the comment about ALPN being the only
cause of such a delay.
Willy Tarreau [Thu, 7 Aug 2025 14:07:37 +0000 (16:07 +0200)]
CLEANUP: backend: clarify the role of the init_mux variable in connect_server()
The init_mux variable is currently used in a way that's not super easy
to grasp. It's set a bit too late and requires to know a lot of info at
once. Let's first rename it to "may_start_mux_now" to clarify its role,
as the purpose is not to *force* the mux to be initialized now but to
permit it to do it.
MEDIUM: server: Introduce the concept of path parameters
Add a new field in struct server, path parameters. It will contain
connection informations for the server that are not expected to change.
For now, just store the ALPN negociated with the server. Each time an
handhskae is done, we'll update it, even though it is not supposed to
change. This will be useful when trying to send early data, that way
we'll know which mux to use.
Each time the server goes down or is disabled, those informations are
erased, as we can't be sure those parameters will be the same once the
server will be back up.
MINOR: ssl: Use the new flag to know when the ALPN has been set.
How that we have a flag to let us know the ALPN has been set, we no
longer have to call ssl_sock_get_alpn() to know if the alpn has been
negociated already.
Remove the call to conn_create_mux() from ssl_sock_handshake(), and just
reuse the one already present in ssl_sock_io_cb() if we have received
early data, and if the flag is set.
MINOR: ssl: Add a flag to let it known we have an ALPN negociated
Add a new flag to the ssl_sock_ctx, to be set as soon as the ALPN has
been negociated.
This happens before the handshake has been completed, and that
information will let us know that, when we receive early data, if the
ALPN has been negociated, then we can immediately create a mux, as the
ALPN will tell us which mux to use.
BUG/MEDIUM: ssl: create the mux immediately on early data
If we received early data, and an ALPN has been negociated, then
immediately try to create a mux if we did not have one already.
Generally, at this point we would not have one, as the mux is decided by
the ALPN, however at this point, even if the handshake is not done yet,
we have enough to determine the ALPN, so we can immediately create the
mux.
Doing so makes up able to treat the request immediately, without waiting
for the handshake to be done.
BUG/MEDIUM: h1: Allow reception if we have early data
In h1_recv_allowed(), do not forbid the reception if we are yet to
complete the connection, if we have received early data on it. That way,
we can deal with them right away, instead of waiting for the handshake
to be done.
MEDIUM: peers: don't even try to process updates under contention
Recent fix 2421c3769a ("BUG/MEDIUM: peers: don't fail twice to grab the
update lock") improved the situation a lot for peers under locking
contention but still not enough for situations with many peers and
many entries to expire fast. It's indeed still possible to trigger
warnings at end of injection sessions for 16 peers at 100k req/s each
doing 10 random track-sc when process_table_expire() runs and holds the
update lock if compiled with a high value of STKTABLE_MAX_UPDATES_AT_ONCE
(1000). Better just not insist in this case and postpone the update.
At this point, under load only ebmb_lookup() consumes CPU, other functions
are in the few percent, indicating reasonable contention, and peers remain
updated.
This should be backported to 3.2 after a bit of testing.
MEDIUM: stick-tables: don't wait indefinitely in stktable_add_pend_updates()
This one doesn't need to wait forever, if it cannot work it can postpone
it. When building with a high value of STKTABLE_MAX_UPDATES_AT_ONCE (1000),
it's still possible to trigger warnings in this function on the write lock
that is contended by peers and expiration. Changing it for a trylock resolves
the issue.
This should be backported to 3.2 after a bit of testing.
MEDIUM: stick-tables: give up on lock contention in process_table_expire()
process_table_expire() can take quite a lot of time running over all
shards. During this time it will hinder track-sc rules and peers, which
will experience an increased latency to do their work, especially peers
where each message will cause a lock, whose cumulated time can exceed
the watchdog's patience.
Here, we proceed just like in stktable_trash_oldest(), which is that
we're using a trylock to detect contention. The first time it happens,
if we hadn't purged anything, we switch to a regular lock to perform
the operation, and next time it happens we abort. This guarantees that
some entries will be expired and that contention will be reduced with
when detected.
With this change, various tests didn't manage to produce any warning,
including at the end of the load generation session.
This should be backported to 3.2 after a bit more testing.
MEDIUM: stick-tables: relax stktable_trash_oldest() to only purge what is needed
stktable_trash_oldest() does insist a lot on purging what was requested,
only limited by STKTABLE_MAX_UPDATES_AT_ONCE. This is called in two
conditions, one to allocate a new stksess, and the other one to purge
entries of a stopping process. The cost of iterating over all shards
is huge, and a shard lock is taken each time before looking up entries.
Moreover, multiple threads can end up doing the same and looking hard for
many entries to purge when only one is needed. Furthermore, all threads
start from the same shard, hence synchronize their locks. All of this
costs a lot to other operations such as access from peers.
This commit simplifies the approach by ignoring the budget, starting
from a random shard number, and using a trylock so as to be able to
give up early in case of contention. The approach chosen here consists
in trying hard to flush at least one entry, but once at least one is
evicted or at least one trylock failed, then a failure on the trylock
will result in finishing.
The function now returns a success as long as one entry was freed.
With this, tests no longer show watchdog warnings during tests, though
a few still remain when stopping the tests (which are not related to
this function but to the contention from process_table_expire()).
With this change, under high contention some entries' purge might be
postponed and the table may occasionally contain slightly more entries
than their size (though this already happens since stksess_new() first
increments ->current before decrementing it).
Measures were made on a 64-core system with 8 peers
of 16 threads each, at CPU saturation (350k req/s each doing 10
track-sc) for 10M req, with 3 different approaches:
- this one resulted in 1500 failures to find an entry (0.015%
size overhead), with the lowest contention and the fairest
peers distibution.
- leaving only after a success resulted in 229 failures (0.0029%
size overhead) but doubled the time spent in the function (on
the write lock precisely).
- leaving only when both a success and a failed lock were met
resulted in 31 failures (0.00031% overhead) but the contention
was high enough again so that peers were not all up to date.
Considering that a saturated machine might exceed its entries by
0.015% is pretty minimal, the mechanism is kept.
This should be backported to 3.2 after a bit more testing as it
resolves some watchdog warnings and panics. It requires precedent
commit "MINOR: stick-table: permit stksess_new() to temporarily
allocate more entries" to over-allocate instead of failing in case
of contention.
MINOR: stick-table: permit stksess_new() to temporarily allocate more entries
stksess_new() calls stktable_trash_oldest() to release some entries.
If it fails however, it will fail to allocate an entry. This is a problem
because it doesn't permit stktable_trash_oldest() to be used in best effort
mode, which forces it to impose high contention. There's no problem with
allocating slightly more in practice. In the worst case if all entries are
in use, it's not shocking to temporarily exceed the number of entries by a
few units.
Let's relax this problematic rule. This patch might need to be backported
to 3.2 after a bit more testing in order to support locking relaxation.
The following functions take locks and are often involved in warnings
but are currently not resolved, so let's export them so that they are
properly decoded:
MINOR: debug: report the time since last wakeup and call
When task profiling is enabled, the current thread knows when the
currently running task was woken up and called, so we can calculate
how long ago it was woken up and called. This is convenient to figure
whether or not a warning or panic is caused by this task or by a
previous one, so let's report this info in thread outputs when known.
MINOR: debug: report the number of loops and ctxsw for each thread
When multiple similar warnings are emitted, it can be difficult to know
whether only one task is looping slowly or if many are sharing the CPU.
Let's report the number of context switches and polling loop turns in
thread dumps so that warnings are easier to understand.
DEBUG: stream: count the number of passes in the connect loop
Normally the connect loop cannot loop, but some recent traces can easily
convince one of the opposite. Let's add a counter, including in panic
dumps, in order to avoid the repeated long head scratching sessions
starting with "and what if...". In addition, if it's found to loop, this
time it will be certain and will indicate what to zoom in. This should
be backported to 3.2.
MINOR: debug: report the process id in warnings and panics
Warning and panic messages currently do not report the PID. This is
annoying when trying to reproduce problems because warnings do not
allow know which process to attach to in order to debug, and panics
do not permit to know which core dump corresponds to which dump.
Let's add them in both messages. This should probably be backported
at least to 3.2.
MINOR: check: reject invalid check config on a QUIC server
QUIC is now supported on the backend side. The previous commit ensures
that simple checks can be activated on QUIC servers without any issue.
The current patch ensures that check server settings remain compatible
with a QUIC server. Thus, configuration is now invalid if check
specifies an explicit MUX proto other than QUIC, disables SSL or try to
use PROXY protocol.
BUG/MINOR: check: ensure checks are compatible with QUIC servers
Previously, checks were only performed on TCP. However, QUIC is now
supported on backend. Prior to this patch, check activation for QUIC
servers would result in a crash.
To ensure compatibility between QUIC servers and checks, adjust
protocol_lookup() performed during check connect step. Instead of using
a hardcoded PROTO_TYPE_STREAM, the value is now derived from server
settings.
BUG/MEDIUM: checks: fix ALPN inheritance from server
If no specific check settings are defined on a server line, it is
expected that these checks will be performed with the same parameters as
normal connections on the same server.
ALPN must be carefully taken into account for checks. Most notably, MUX
initialization is delayed so that it is performed only after SSL
handshake.
Prior to this patch, MUX init delay was only performed if ALPN was
defined via check settings. Thus, with the following settings, checks
would be performed on HTTP/1.1 without consulting ALPN negotiation
result from the server :
server s1 127.0.0.1:443 ssl crt <...> alpn h2 check
This bug may result in checks reporting failure, for example in case of
a server answering HTTP/2 to ALPN negotiation to the configuration
above. Besides, there is incoherency between normal and check
connections, which is not what the documentation specifies.
This patch fixes this code. Now server parameters are also taken into
account. This ensures that checks and normal connections by default
use the same connection method.
OPTIM: check: do not delay MUX for ALPN if SSL not active
To ensure ALPN is properly applied on checks, MUX initialization is
delayed so that it is created on SSL handshake completion. However, this
does not check if SSL is really active for the connection.
This patch adjusts the condition so that MUX init is not delayed if SSL
is not active for the check connection. A similar process is already
conducted for normal connections via connect_server().
This must be backported up to 2.4. Despite not being a bug, it must be
backported for the following patch which fixes check ALPN inheritance
from server settings.
BUG/MINOR: hq-interop: adjust parsing/encoding on backend side
HTTP/0.9 is available on top of QUIC. This protocol is reserved for
internal use, mostly interop purpose.
This patch adjusts HTTP/0.9 layer with the following changes :
* version is not emitted anymore on the status line. This is performed
as some servers does not parse it correctly.
* status line is set explicitely on HTX status-line. This ensures the
correct HTTP status code is reported to the upper stream layer.
BUG/MEDIUM: mux-h2: Reinforce conditions to report an error to app-layer stream
This patch relies on the previous one ("BUG/MEDIUM: mux-h2: Report RST/error to
app-layer stream during 0-copy fwding").
When the end of the connection is detected, so when the H2_CF_END_REACHED
flag is set after the shutdown was received and all incoming data were
processed, if a stream is blocked by the flow control (the stream one or the
connection one), an error must be reported to the app-layer stream.
Otherwise, outgoing data won't be sent and the opposite side will handle
this as a lack of room. So the stream will be blocked until the write
timeout is triggerd. By reporting the error early, the stream can be
immediately closed.
This patch should be backported to 3.2. For older versions, it is probably a
good idea to wait for bug report.
BUG/MEDIUM: mux-h2: Report RST/error to app-layer stream during 0-copy fwding
In h2_nego_ff(), it is important to report reset and error to app-layer
stream and to send the RST-STREAM frame accordingly. It is not clear if it
is an issue or not. But it is clearly a difference with the classical
forwarding via h2_snd_buf. And it is mandatory for the next fix.
This patch should be backported to 3.2. But is is probably a good idea to
not backport it on older versions, except if a bug is reported in this area.
BUG/MINOR: mux-h2: Remove H2_CF_DEM_DFULL flags when the demux buffer is reset
This only happens when a connection error is detected or when the H2
connection is in ERR/ERR2 state. The demux buffer is explicitly reset. In
that case, it is important to remove the flag reporting this buffer as full.
It is probably worth to backport this patch to 3.2. But it is not mandatory
on older versions because it does not fix any known issue.
BUG/MEDIUM: mux-h2: Restart reading when mbuf ring is no longer full
When the mbuf ring buffer is full, the flag H2_CF_DEM_MROOM is set on the H2
connection to block any demux. It is important to properly handle ACK
frames. However, we must take care to restart reading when some data were
removed from the mbuf. Otherwise, we may block the demux for no reason. It
is especially an issue if the demux buffer is full. In that case, the H2
connection is blocked, waiting for the timeout.
This patch should be backported to 3.2. But is is probably a good idea to
not backport it on older versions, except if a bug is reported in this area.
BUG/MEDIUM: mux-h2; Don't block reveives in H2_CS_ERROR and H2_CS_ERROR2 states
The H2 connection is switched to ERR when a GOAWAY must be sent and in ERR2
when it is sent. In these states, no more data can be emitted by the
mux. But there is no reason to not try to process incoming data or to not
try to receive data. It is espcially important to be able to get the
shutdown from the TCP connection when a SSL connection was previously
detected. Otherwise, it is possible to block a H2 connection until its
timeout expiration to be able to close it.
This patch should be backported to 3.2. But is is probably a good idea to
not backport it on older versions, except if a bug is reported in this
area.
BUG/MEDIUM: mux-h2: Reset MUX blocking flags when a send error is caught
When an send error is detected on the underlying connection, a pending error
is reported to the H2 connection by setting H2_CF_ERR_PENDING flag. When
this happen the tail of the mux ring buffer is reset. However some blocking
flags remain set and have no chance to be removed later because of the
pending error. Especially the flag H2_CF_DEM_MROOM which block data
demultiplexing. Thus, it is possible to block a H2 connection with unparsed
incoming data.
Worse, if a read event is received, it could lead to a wakeup loop between
the H2 connection and the underlying SSL connection. The H2 connection is
unable to convert the pending error to a fatal error because the
demultiplexing is blocked. In the mean time, it tries to receive more data
because of the not-consumed read event. On the underlying connection side,
the error detected earlier blocks the read, but the H2 connection is woken
up to handle the error.
To fix the issue, blocking flags must be removed when a send error is caught,
H2_CF_MUX_MFULL and H2_CF_DEM_MROOM flags. But, it is not necessary to only
release the tail of the mbuf ring. When a send error is detected, all outgoing
data can be flushed. So, now, in h2_send(), h2_release_mbuf() function is called
on pending error. The mbuf ring is fully released and H2_CF_MUX_MFULL and
H2_CF_DEM_MROOM flags are removed.
Many thanks to Krzysztof Kozłowski for its help to spot this issue.
This patch could be backported at least as far as 2.8. But it is a bit
sensitive. So, it is probably a good idea to backport it to 3.2 for now and
wait for bug report on older versions.
BUG/MINOR: quic: properly support GSO on backend side
Previously, GSO emission was explicitely disabled on backend side. This
is not true since the following patch, thus GSO can be used, for example
when transfering large POST requests to a HTTP/3 backend.
However, GSO on the backend side may cause crash when handling EIO. In
this case, GSO must be completely disabled. Previously, this was
performed by flagging listener instance. In backend side, this would
cause a crash as listener is NULL.
This patch fixes it by supporting GSO disable flag for servers. Thus, in
qc_send_ppkts(), EIO can be converted either to a listener or server
flag depending on the quic_conn proxy side. On backend side, server
instance is retrieved via <qc.conn.target>. This is enough to guarantee
that server is not deleted.
MINOR: pools: Don't dump anymore info about pools when purge is forced
Historically, when the purge of pools was forced by sending a SIGQUIT to
haproxy, information about the pools were first dumped. It is now totally
pointless because these info can be retrieved via the CLI. It is even less
relevant now because the purge is forced typically when there are memroy
issues and to dump pools information, data must be allocated.
dump_pools_info() function was simplified because it is now called only from
an applet. No reason to still try to dump info on stderr.
BUG/MINOR: pools: Fix the dump of pools info to deal with buffers limitations
The "show pools" CLI command was not designed to dump information exceeding
the size of a buffer. But there is now much more pools than few years ago
and when detailed information are dumped, we exceeds the buffer limit and
the output is truncated.
To fix the issue, the command must be refactored to be able to stream the
result. To do so, the array containing pools info is now part of the command
context and it is dynamically allocated. A dedicated function was created to
fill all info. In addition, the index of the next pool to dump is saved in
the command context too to properly handle resumption cases. Finally global
information about pools are also stored in the command context for
convenience.
This patch should fix the issue #3067. It must be backported to 3.2. On
older release, the buffer limit is never reached.
REGTESTS: ssl: Fix the script about automatic SNI selection
First, the barrier to delay the client execution was moved before the client
definition. Otherwise, the connection is established too early and with
short timeouts it could be closed before the requests are sent.
The main purpose of the barrier was to workaround slow health-checks. This
is also the reason why the script was flagged as slow. But it can be
significantly speed-up by setting a slow "inter" value. It is now set to
100ms and the script is no longer slow.
The below patch fixes padding emission for small packets, which is
required to ensure that header protection removal can be performed by
the recipient.
In addition to the proper fix, constant QUIC_HP_SAMPLE_LEN was removed
and replaced by QUIC_TLS_TAG_LEN. However, it still makes sense to have
a dedicated constant which represent the size of the sample used for
header protection. Thus, this patch restores it.
Special instructions for backport : above patch mentions that no
backport is needed. However, this is incorrect, as bug is introduced by
another patch scheduled for backport up to 2.6. Thus, it is first
mandatory to schedule d7dea408c64c327cab6aebf4ccad93405b675565 after it.
Then, this patch can also be used for the sake of code clarity.
Define a new "quic_tx" unit-test which is used to test QUIC TX module.
For the moment, a single test is performed on qc_do_build_pkt(). It
checks that PADDING is correctly added for HP sampling in case of a
small packet.
MINOR: stats-file: use explicit unsigned integer bitshift for user slots
As reported in GH #3104, there remained a place where (1 << shift was
used to set or remove bits from uint64_t users bitfield. It is incorrect
and could lead to bugs for values > 32 bits.
Instead, let's use 1ULL to ensure the operation remains 64bits consistent.
BUG/MEDIUM: proxy: fix crash with stop_proxy() called during init
Willy reported that the following config would segfault right after the
"removing incomplete section 'peer' is emitted:
peers peers
bind :2300
server n10 127.0.0.1:2310
listen dummy
bind localhost:9999
This is caused by the fact that stop_proxy(), which tries to read shared
counters, is called during early init while shared counters are not yet
initialized. To fix the crash, let's check if we're still during starting
phase, in which case we assume the counters are not initialized and we
assume 0 value instead.
No backport needed unless 16eb0fab31 ("MAJOR: counters: dispatch counters
over thread groups") is.
Mimic the same behavior as the one for SSL/TCP connetion to implement the
SSL session reuse.
Extract the code which try to reuse the SSL session for SSL/TCP connections
to implement ssl_sock_srv_try_reuse_sess().
Call this function from QUIC ->init() xprt callback (qc_conn_init()) as this
done for SSL/TCP connections.
When kTLS is compiled in, make sure msg_controllen is initialized to 0.
If we're not actually kTLS, then it won't be set, but we'll check that
it is non-zero later to check if we ancillary data.
This does not need to be backported.
This should fix CID 1620865, as reported in github issue #3106.
BUG/MINOR: cpu_topo: work around a small bug in musl's CPU_ISSET()
As found in GH issue #3103, CPU_ISSET() on musl 1.25 doesn't match the man
page which says it's returning an int. The reason is pretty simple, it's
a macro that operates on the bits directly and returns the result of the
bit field applied to the mask as an unsigned long. Bits above 31 will
simply be dropped if returned as an int, which causes CPUs 32..63 to
appear as absent from cpu_sets.
The fix is trivial, it consists in just comparing the result against zero
(i.e. turning it to a boolean), but before it's merged and deployed we'll
have to face such deployments, so better implement the same workaround
in the code here since we have access to the raw long value.
BUG/MINOR: quic: too short PADDING frame for too short packets
This bug arrvived with this commit:
MINOR: quic: centralize padding for HP sampling on packet building
What was missed is the fact that at the centralization point for the
PADDING frame to add for too short packet, <len> payload length already includes
<*pn_len> the packet number field length value.
So when computing the length of the PADDING frame, the packet field length must
not be considered and added to the payload length (<len>).
This bug leaded too short PADDING frame to too short packets. This was the case,
most of times with Application level packets with a 1-byte packet number field
followed by a 1-byte PING frame. A 1-byte PADDING frame was added in this case
in place of a correct 2-bytes PADDINF frame. The header packet protection of
such packet could not be removed by the clients as for instance for ngtcp2 with
such traces:
I00001828 0x5a135c81e803f092c74bac64a85513b657 pkt could not decrypt packet number
As the header protection could no be removed, the header keyupdate bit could also
not be read by packet analyzers such as pyshark used during the keyupdate tests.
REGTESTS: ssl: Add a script to test the automatic SNI selection
The script reg-tests/ssl/ssl_sni_auto.vtc tests the automatic SNI selection
for regular server connections and for health-check ones. It rely on a
3.3-dev8 feature (in fact, it was pushed just after the dev8).
MEDIUM: httpcheck/ssl: Base the SNI value on the HTTP host header by default
Similarly to the automic SNI selection for regulat SSL traffic, the SNI of
health-checks HTTPS connection is now automatically set by default by using
the host header value. "check-sni-auto" and "no-check-sni-auto" server
settings were added to change this behavior.
Only implicit HTTPS health-checks can take advantage of this feature. In
this case, the host header value from the "option httpchk" directive is used
to extract the SNI. It is disabled if http-check rules are used. So, the SNI
must still be explicitly specified via a "http-check connect" rule.
This patch with should paritally fix the issue #3081.
MEDIUM: server/ssl: Base the SNI value to the HTTP host header by default
For HTTPS outgoing connections, the SNI is now automatically set using the
Host header value if no other value is already set (via the "sni" server
keyword). It is now the default behavior. It could be disabled with the
"no-sni-auto" server keyword. And eventually "sni-auto" server keyword may
be used to reset any previous "no-sni-auto" setting. This option can be
inherited from "default-server" settings. Finally, if no connection name is
set via "pool-conn-name" setting, the selected value is used.
The automatic selection of the SNI is enabled by default for all outgoing
connections. But it is concretely used for HTTPS connections only. The
expression used is "req.hdr(host),host_only".
This patch should paritally fix the issue #3081. It only covers the server
part. Another patch will add the feature for HTTP health-checks.
BUG/MINOR: tcpcheck: Don't use sni as pool-conn-name for non-SSL connections
When we try to ruse connection to perform an healtcheck, the SNI, from the
tcpcheck connection or the healthcheck itself, must not be used as
connection name for non-SSL connections.